1. Field of the Invention
The invention generally relates to capacitors, and more specifically to carbon nanotubes for use therein.
2. Description of the Related Art
Carbon nanotubes (hereinafter referred to also as “CNTs”) are carbon structures that exhibit a variety of properties. Many of the properties suggest opportunities for improvements in a variety of technologies. For example, technologies that benefit from increased strength, conductivity or capacitance will benefit from the use of CNT. Accordingly, advances in CNT technology are of great interest to those working with capacitors.
Capacitors are one of the key components in a variety of electric systems. Functions include power buffering, energy storage, and voltage smoothing. A variety of industries present demanding requirements for capacitors.
Consider, for example, that industries such as automotive, manufacturing, aerospace, aviation, medical, and military have some applications that require capacitors to provide energy or power support for electrified drive, pulse power, or process actuation. Energy capacity and power capability are key requirements in typical applications within those industries. Applications such as providing torque assist in electrified drivetrains, power-assist for motor drives in manufacturing plants, or voltage support during high power load demands, require substantial energy and power. Some applications present limited physical space or upper bounds on weight. Some applications require long cycle life.
Thus, capacitors used in industrial environments must meet demands for performance while meeting physical constraints. For designers and producers of utlracapacitors, one of the attendant challenges is obtaining an electrode that will function at a desired output.
Thus, what are needed are methods and apparatus for production of a high power electrode based on carbon nanotubes. Preferably, the methods and apparatus are simple to perform and thus offer reduced cost of manufacture, as well as an improved rate of production. Preferably, the methods and apparatus provide for electrodes for ultracapacitors that perform well in demanding situations. Preferably, the electrodes provide stable conductivity and low internal resistance over a wide range of temperatures.